Valve mechanism for internal-combustion engines



April 21, 1925.

' w. B. EARNSHAW VALVE mzcmmxsm FOR INTERNAL COMBUSTION ENGINES Filed Marci; s, 1921 2 Sheets-Sheet 1 April 21, 1925. 1,534,773 w. B. EARNSHAW' Y VALVE mcamnxsm FOR lN'I'ERNAL comausnou ENGINES) Filed March 5, 1921 2 Sheets-Sheet 2 swi Patented Apr. 21, 1925.

UNI-TED STATES PAT "OF-FTCE;

WILLIAM B; EAR/NSHAW', OF" DAYTON; OHIO, ASSIGNO'R T;O GENERAL MOTORS RE- SEARCH CORPORATION, OFiDAFYeTQN", OHIO, A CORPORATION OF DELAWARE.

VALVE MECHANISMv FOR INTERNAL-COMBUSTION: ENGINES.

Application filed' March 3, 1921'.

To all whom it may concern:

Be it known that I, l/VILLIAM B. EARN- SHAW, a citizen of the United Statesof America, residing at Dayton, county of 5 Montgomery and State of Ohio, have invented certain new and useful Improvements in Valve Mechanism for Internal-Combustion Engines, of which the following is a full, clear, and exact description.

The present invention relates to improvements in internal-combustion engines and in its preferred form of embodiment which has been chosen for the purposes of description and illustration, relates particularly to means for reducing wear upon certain parts of the valve mechanism.

The objects of the invention include elimination of sliding contact of the rocker arm with the valve stem and also reduction of wear on that portion of the rocker arm which ordinarily contacts with the said stem.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.

In the drawings:

Fig. 1 shows a conventional representation of the cylinder of an internal-combustion engine with part of the valve mechanism in section.

Fig. 2 is a plan view of a portion of an internal-comlmstion engine showing the two rocker arms operating the valves in one of the cylinders.

Fig. 3 is a vertical section through Fig. 2 on the line 3-3, part of the elements on said line being shown in elevation and not in section.

The device forming the preferred form of embodiment of the present invention is illustrated very clearly in the drawings and consists of a bar forming part of the casting which supports the rocker arms 11 andqrocker arm shafts 12. This bar is drilled and counterbored opposite each valve loca tion and in the direction of the motion of the valve as is indicated at 13 in Figs. 1 and 3. In the hole or socket thus provided, is placed a plunger 14 having a small portion 15 adapted to make a good sliding fit. The upper end of this plunger provides a large flat surface upon which acts the valve end 16 of rocker arm 11 and being large and Serial No. 449,441;

offering a good surface for rolling contact with the end of the rocker arm tends to reduce wear. caused'bythe sliding and. rolling motion.

Itwill be noted. that the valve end- 16. of therocker arm-is extended laterally so as to greatly increase the surface in contact with the plunger 14. By increasing the area of contact surface, one of the advantages will be to tend to reduce the depth of wear at the point of contact of the rocker arm and the plunger, thus minimizing adjustments.

The extended portion 15 of the plunger 14 rests upon the upper end of the valve stem 20. Thus, as the axis of the socket 13 is substantially in alignment and preferably coincident with the axis of the valve stem, :1. straight push is exerted by the plunger 14 upon the valve stem 20, reducing the wear on the valve stem and its guide 21, also on the end of the valve stem which contacts with the end 15 of the plunger 14 and also upon the bottom portion 15.

Thus, even if there be wear between the plungers 14 and their sockets 13, the wear of the valve stems and guides is reduced and this is very desirable, since due to the plungers imparting straight thrusts to the valves, the side play of the valve stemsis substantially eliminated and the number of replacements of the valves is greatly lessened. If desirable, replacements of the plungers 14 may be made, and it is evident that the cost relative to the cost of replacing the valves is greatly reduced and that the number of replacements of these plungers will be materially less than the replacements of the valves necessary in the conventional constructions.

It will be seen that by the present invention there has been provided means simple in construction, efficient in operation, and easily and economically produced. It will also be seen that this construction will greatly reduce wear on the I valve stems, guides, and rocker arms, then eliminating frequent adjustment and reducing the cost of up-keep.

It is obvious that other means of reducing the wear upon the valve stems and rocker arms might be substituted, in whole or in part, without materially departing from the spirit of the present invention.

:Vhile the form of mechanism herein shown and described constitutes a preferred form of embodiment of the present invention, it is to be understood that other forms might be adopted, all coming within the scope of the claim which follows.

What I claim is as follows:

In valve operating mechanism of the class described and in combination with an engine cylinder having an intake and an exhaust valve in the head thereof and movable parallel with the axis of the cylinder, a supporting member carried by said cylinder and arranged above the head thereof; a plunger carrying bar carried by said supporting member and arranged above said valves, and having bearings arranged in line with the paths of movement of said valves; recipro- WILLIAM B. EARNSHAV.

Witnesses:

L. H. EMRIGK, R. K. LEE. 

